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BEIJING, Jan. 3 (Xinhua) -- The concentrations of Beijing's four major air pollutants including PM2.5 and PM10 continued to fall remarkably in 2019, the capital's Municipal Ecology and Environment Bureau announced at a press conference Friday.

The average concentration of PM2.5 was 42 micrograms per cubic meter last year, dropping by 53 percent over 2013, the year a national action plan was issued by the State Council to fight air pollution, according to the bureau.

Four days of heavy air pollution were recorded and no heavy air pollution was recorded for 280 consecutive days.

The average concentration of PM10, nitrogen dioxide and sulfur dioxide were 68, 37 and 4 micrograms per cubic meter respectively, said Liu Baoxian, head of the Beijing Municipal Environmental Monitoring Center.

The average concentration of PM2.5 in Beijing's Miyun District and Huairou District were 34 and 35 micrograms per cubic meter in 2019, Liu added.

In 2019, the share of good air quality days stood at 65.8 percent, totaling 240 days, Liu said.

Throughout the year, Beijing only saw four days of heavy air pollution in winter and autumn, with PM2.5 remaining the major pollutant, Liu added.